Around $1200 new. D2 is enough for a fixed top in nearly any temp one be out skiing in. It is enough for a pop top to around perhaps minus 5 or 10. It will run at the higher end longer but you will be toasty warm. This info would be for a reasonably insulated van.
Beastie 3: 2002 7.3 EB Cargo: Agile TTB, CCV Mid Top, Custom Walk Through, Lots of stuff added. BlingMyRig.com